A Solar Attic Fan
Why Do You Need it?

What is a Solar Attic Vent?

The solar attic fan use sun power to ventilate out the hot air from the attic space.

Summer time, long hours of intense sun radiation is hitting the roof and the attic space is getting hotter and hotter. Evening comes, sun sets and the attic space is extremely hot. Temperatures soaring to 150 degrees F (65 degrees C) were reported. The attic space is supposed to be isolated and thermally insulated from the main building space. Well, nothing is perfect and eventually heat from the attic leaks into the home space. So, the air-conditioner "works overtime" and somebody (you I'm afraid) is paying the bill.
The old time solution was the fan, the roof ventilator or any other passive (driven by occasional wind breeze) ventilator.
You can do better; buy and install an active fan. The solar attic vent is a ventilator that has its own small solar "power plant", a small size solar electric panel. It is installed the same way as the passive ventilator and vents out hot air from the attic to the external world actively. The advantages:

• Guaranteed operation, independent on occasional wind


• Synchronized with the sun, the sun is the remedy to the heat accumulation caused by the sun; therefore, battery backup for the night is not needed


• Self contained; except for a mounting flange on the roof nothing else is required; no wiring is needed from the house to the attic


• A 20 Watts fan can adequately vents out a 1500 square feet attic

Points to watch

1. Buy from a manufacturer that has good reputation


2. Look into the ease and flexibility of installation


3. See what is the warranty period (repair or replace)


4. Examine the spec sheet: Watts, air flow (CFM) and size the fan can vents out from (square feet)


5. Caveat: in case the attic space is not really separate from the main building space (in other words they form a one big space) a solar attic fan will not perform an efficient job
6. Active fans can replace existing passive fans or added; read the vendor installation guide to find the optimal mounting position.
7. Price; expect a return on investment in 2 years (by saving on air conditioning bills)

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